Not sure if I posted this in the right forum. I went to take the muzzle loaders out to the range and found my last 1/2 lb of 4F powder was hardened. I've had the stuff for over 10 yrs. but must have not closed the container tightly the last time I used it. Where can I get real black powder in the FFFF or FFF grain size for my flintlock? Any old school black powder shooters out there that might know?